{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# quiz8sol - November14,2007 PHY2053 Quiz8(Chapter8 Name:UFID...

This preview shows pages 1–2. Sign up to view the full content.

November 14, 2007 PHY2053  Quiz 8 (Chapter 8) Name:                                   UFID: 1. (5 pts) A 20.0m, 40.0kg uniform ladder rests against a frictionless wall, making an  angle of 60º with the horizontal. Find the minimum coefficient of static friction between  ladder and ground so that a 80.0 kg firefighter can reach the top of the ladder. Since each component of the net force equals zero, we get X: n-mg-Mg = 0   n = (m+M)g = (80+40)9.8 = 1176 N, Y: N-f = 0   f = N,  where m = 80kg, M = 40kg, n/N are the normal force from the ground/the wall.  Now we calculate the torque around the bottom of the ladder when the firefighter   reaches the top: mgLcos +Mg(L/2)cos -NLsin  = 0  θ θ θ  N = (gcos (m+M/2))/sin  = 9.8cos60º(80+40/2)/sin60º = 565.8 N θ θ

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern